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Posts Made By: Herbert Kraus

February 7, 2006 08:53 AM Forum: Deep Sky Observing

Sagittarius DSO's

Posted By Herbert Kraus

My observing logs for non-Messier objects in Sagittarius contain these references:
I noted NGC 6520 (to which which someone else has also referred you) as a small but "fine" open cluster with several prominent stars among a swarm of unresolved members (viewed in an 8-inch SCT at 135x). Archinal & Hynes says it contains 60 stars within a diameter of 5 arcminutes.
NGC 6440 (also viewed at 135x) is a globular that I couldn't resolve (nor could a Webb Society observer using a 16½-inch scope at 222x), but which fascinated me because when I viewed it through a wider-angle eyepiece (83x) I saw it as the middle one in a string of five 10th magnitude objects.

February 8, 2006 10:47 AM Forum: Deep Sky Observing

DSO's in Vela, Puppis, Pyxis, Antlia

Posted By Herbert Kraus

Inge: In Puppis: by all means look at M93; it's big and bright and, according to Archinal & Hynes, contains 80 stars within a 10-arcminute diameter. On the double star front, if you like Gamma Arietis don't miss its cousin, k Puppis, a pair of magnitude 4½ white stars (about 9 arcseconds apart) with a bonus thrown in if you can see it: a 14th magnitude star 7 arcseconds away from one of the two bright ones.

February 15, 2006 12:48 PM Forum: Solar System Observing

Red dot over the Moon

Posted By Herbert Kraus

Carlos: I could not see the red dot on the second of your two posts, but I did a quick calculation based on the change in the dot's position on the first images you posted, and was surprised to conclude that the change may be inconsistent with the belief that the dot is an artifact attributable to your film or camera. Don't take these data too seriously, but here's what I did: The dot appears to have moved in a westerly direction (the direction you would expect it to move if it were just a photographic artifact) a distance approximately equal to the diameter of crater Copernicus during what you estimated as a 20 second time difference between the two images; the angular diameter of Copernicus seen from earth is around 49 arcseconds; based on moon's sidereal orbital period of 29.53 days, during 20 seconds of time the moon, or any point on its surface, as seen from the earth would move in an easterly direction through about 10.16 arcseconds. It would therefore seem that during a period of about 20 seconds the red dot seemed to change its position by about 49 arcseconds but, if the dot was attributable to an artifact in your film or camera, that change in position should have been only about 10.16 arcseconds. The implication would be that the red dot was indeed a satellite (or any kind of other extra-terrestial phenomenon that it amuses you to speculate about).

February 21, 2006 07:27 PM Forum: After Dark

Sadness & Fear

Posted By Herbert Kraus

I am not privy to what led to the sale of Sky & Telescope, but the news release indicated that the buyers are a group of Boston venture capitalists who plan to assemble a group of special interest magazines, of which S&T is the first. This could be the best possible news for serious amateur astronomers, like me and most of you, who like S&T and its features and don't want to see it descend into a fluffy pop-science journal that caters to a low common denominator mass audience so it can pay its bills by attracting the most advertising dollars. The apparent business plan of the buyers, combining S&T with other special but limited interest periodicals, may very well be the best way to guarantee S&T's continuing viability as a premier source for serious science that is of interest to the community of amateur astronomers.

February 24, 2006 10:09 PM Forum: Landscape Photography

North Pole, Moon, Sun

Posted By Herbert Kraus

A beautiful image, indeed. My wild guess is that it's a picture of the summer night sun at some arctic location (but not the North Pole, with so broad an expanse of liquid water and a horizon that looks like some land masses rather than ice), and that the "moon" is the partially illuminated bottom cowl of the jet plane that brought the photographer to this location). Still, it's pretty enough.

March 19, 2006 01:09 PM Forum: Off Topic Discussions


Posted By Herbert Kraus

Ron: Saqsaywaman, the site depicted in your fine photos, is just outside of Cusco, so I must presume that you also visited Machu Picchu while in Peru. If so, you saw more of the same impressive masonry work, this time at a much more inaccessible site. There are other examples of Inca masonry, such as at Ollantaytambo which lies in the Urubamba Valley between Cusco and Machu Picchu. Although the quality of this work is almost beyond belief, the evidence is rather overwhelming that the Incas did indeed build these marvelous structures. Perhaps it is we, with our assumption that such construction was made possible only by the post-industrial revolution's technology, who need to be reminded that neither the Incas nor the ancient Egyptians nor the Mayans, etc. required such technology.

April 5, 2006 10:15 AM Forum: Deep Sky Observing

A conspiracy?

Posted By Herbert Kraus

Inge: The real problem is that we were all born several centuries too soon. In the distant future, every amateur astronomer will be able to obtain his own space telescope (for the price of a couple of Al Nagler's eyepieces), and, sitting at his computer, will be able to observe DSOs, doubles and other celestial wonders at excellent resolution without regard to such inconveniences as the latitude or the time zone or the atmospheric conditions of his home base. Of course, this assumes that our technology will continue to progress and not be demolished by the extinction of homo sapiens owing to either a stray asteroid or the malfunction of human culture.

April 9, 2006 07:31 PM Forum: Refractors

Orion 80 ED

Posted By Herbert Kraus

Observing at my light-polluted location with the 80ED, I mostly use the Nagler 9mm eyepiece (at 67x) for double stars and the occasional open cluster. Earlier this week, with the moon around first quarter, I looked at Saturn with a 6 mm Ortho (100 x) and then added a 2x barlow. This gave me a power of 200x and allowed me to make out the Cassini Division and the planet's shadow on its rings. That may be the limit of what I can expect of the 80ED at this location, but I suspect it can do even better under dark clear skies.

April 18, 2006 08:11 AM Forum: CCD Imaging and Processing/Deep Sky

M 13

Posted By Herbert Kraus

Dan: Superb! Being a strictly visual observer, I congratulate you particularly on producing an image that comes close to the actual appearance of M13 (when viewed under perfect dark sky conditions), and the inclusion of galaxy NGC 6207 which has been beyond my visual reach.

April 25, 2006 08:47 PM Forum: Equipment Talk

Finding Y Canum Venatacorum with SkyCommander

Posted By Herbert Kraus

Bill: I don't know what SC (SkyCommander?) is, but if it is a kind of digital setting circle or a "go to" device, maybe the following will help:
First, if you want a list of carbon stars with their Epoch 2000 celestial coordinates, try
Second, if SC is a device that can direct your scope to individual stars in the SAO catalog, you might use the resource I use. It's at
Using that site to obtain the SAO catalog numbers of stars whose coordinates you know (whether epoch 2000 or 1950) takes a little study and practice, but it works very well for me now. Incidentally, if you like I can privately email to you the SAO numbers of Y CVn and a number of other carbon stars that may be on you agenda. Regards, Herbert Kraus